首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1546篇
  免费   18篇
  国内免费   27篇
社会科学   1591篇
  2023年   39篇
  2022年   328篇
  2021年   75篇
  2020年   34篇
  2019年   65篇
  2018年   51篇
  2017年   43篇
  2016年   21篇
  2015年   30篇
  2014年   41篇
  2013年   100篇
  2012年   67篇
  2011年   64篇
  2010年   51篇
  2009年   84篇
  2008年   70篇
  2007年   79篇
  2006年   63篇
  2005年   46篇
  2004年   56篇
  2003年   39篇
  2002年   36篇
  2001年   31篇
  2000年   27篇
  1999年   9篇
  1998年   6篇
  1997年   5篇
  1996年   5篇
  1995年   6篇
  1994年   2篇
  1993年   3篇
  1992年   1篇
  1991年   5篇
  1990年   2篇
  1989年   3篇
  1988年   2篇
  1984年   1篇
  1979年   1篇
排序方式: 共有1591条查询结果,搜索用时 15 毫秒
41.
This study examines how the effect of CEO duality on firm performance is affected by two internal governance forces – namely other executives in the top management team and blockholding outside directors. Results based on a longitudinal dataset from the U.S. computer industry were consistent with my hypotheses. Specifically, I found that the effect of CEO duality was negative when the CEO had dominant power relative to other executives and when the board had a blockholding outside director, but was nonsignificant otherwise. This study enriches our understanding of the effect of CEO duality, and helps reinforce the call for the nonduality structure as the default choice and put the burden of proof on those who wish to justify otherwise on special grounds.  相似文献   
42.
43.
Lack of data on daily inhalation rate and activity of children has been an issue in health risk assessment of air pollutants. This study aimed to obtain the daily inhalation rate and intensity and frequency of physical activity in relation to the environment in Japanese preschool children. Children aged four–six years (n= 138) in the suburbs of Tokyo participated in this study, which involved three days' continuous monitoring of physical activity using a tri‐axial accelerometer and parent's completion of a time/location diary during daily life. The estimated three‐day mean daily inhalation rate (body temperature, pressure, saturated with water vapor) was 9.9 ± 1.6 m3/day (0.52 ± 0.09 m3/kg/day). The current daily inhalation rate value of 0.580 m3/kg/day proposed for use in health risk assessment in Japan is confirmed to be valid to calculate central value of inhaled dose of air pollutants in five‐ to six‐year‐old children. However, the 95th percentile daily inhalation rate of 0.83 m3/kg/day based on measurement for five‐year‐old children is recommended to be used to provide an upper bound estimate of exposure that ensure the protection of all five‐ to six‐year‐old children from the health risk of air pollutants. Children spent the majority of their time in sedentary and light level of physical activity (LPA) when indoors, while 85% of their time when outdoors was spent in LPA and moderate‐to‐vigorous physical activity. The results suggest the need to consider variability of minute respiratory ventilation rate according to the environment for more refined short‐term health risk assessment.  相似文献   
44.
45.
In previous work we established a closed-form optimal stocking strategy for an EPQ model with partial backordering at a constant rate β. Here we extend this work to allow for the possibility that the percentage of demand backordered will increase when production starts again. We show how our previous model can be adapted to find the optimal decision variable values for this new assumption and develop the condition that the initial value of β must meet for partial backordering to be optimal.  相似文献   
46.
This paper contributes to our understanding of an increasingly prevalent work system, web-based internet communities (WebICs). We are particularly interested in how WebICs are governed given the fact how different they are compared to more classical forms of organization. We study the governance of a WebIC by studying the structure and dynamics of their edit network. Given the fact that the edit network is a relational structure, social network analysis is key to understanding these work systems. We demonstrate that characteristics of the edit network contribute to predicting the dropout hazard of valuable WebIC members. Since WebICs exist only thanks to the activity of their contributors, predicting drop-outs becomes crucial. The results show that reputation and controversy have different effects for different types of Wikipedians; i.e., an actor’s reputation decreases the dropout hazard of active Wikipedians, while participation on controversial pages decreases the dropout hazard of highly active Wikipedians.  相似文献   
47.
本文以供应链质量成本为主要研究对象,分析归纳供应链质量成本研究现状,结合卓越绩效模式方法,提出质量成本核算体系,建立基于卓越绩效模式的供应链质量成本模型。通过一个应用案例,采用遗传算法求解,证明该方法使供应链成本得到了优化。  相似文献   
48.
针对我国短期利率易受政策影响,波动较大并存在结构变化等特点,构建了跳跃-扩散-机制转换模型,同时考察了银行间7天同业拆借利率的波动、跳跃和结构变化三种效应,发现我国同业拆借利率不仅具有均值回归特性而且还存在明显的跳跃与机制转换,并且该模型比其嵌套的受限模型表现更佳.在高波动状态下利率波动的水平效应和ARCH效应可以忽略...  相似文献   
49.
纳税筹划是实务界与学术界共同关心的领域,现有研究大量讨论了公司纳税筹划行为的决定因素及其经济后果,但仍存在巨大争议。一方面,纳税筹划节约了现金流,提升股东价值;另一方面,代理问题使企业的纳税筹划方案更可能有利于控股股东或管理层,而非上市公司利益最大化,从而可能降低企业价值,最终纳税筹划方案的经济后果取决于上述两方面的共同作用。本文基于某上市公司(J有限公司)收购大股东土地案例,分析了代理成本影响公司税务决策的路径及其经济后果。本文发现,控股股东构造了较为复杂的股权转移交易方式,为上市公司和控股股东节约了大量税务成本。但由于代理成本的存在,在多种纳税筹划方案中,控股股东并未选择对上市公司最为有利的方案,而选择了能够取得现金最多,控股股东利益最大化的方案。进一步的研究发现,市场非常关注该企业的纳税筹划行为,与本文搜集的对照样本相比,尽管J公司的控股股东未选择最优的方案,但投资者仍给予了该纳税筹划行为以积极反应,提升了企业价值。本文为研究代理成本影响公司税务决策的机理提供了重要参考。  相似文献   
50.
本文采用我国制造业上市公司2001年-2007年共2401个公司年的平衡面板数据,利用行业间竞争、行业内竞争两个维度的产品市场竞争变量,实证分析了我国制造业上市公司产品市场竞争对现金持有水平的综合影响。实证结果显示,对于所有制造业上市公司来说,产品市场竞争对公司现金持有存在显著的掠夺风险效应。在考虑公司融资约束的情况下,产品市场竞争对公司现金持有的掠夺风险和代理成本两种竞争效应被有效区分开来。融资约束公司表现为显著的掠夺风险效应,非融资约束公司则表现为显著的代理成本效应。这些研究结论不仅丰富和补充了产品市场竞争与公司现金持有之间的相关研究,也为公司实施积极的现金流风险管理和持有现金的高效利用提供了实践支持。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号